The Use of Constant-flow Technique for Determining the Lower Inflexion Point of Pressure-volume Curve and Intrinsic PEEP During One-lung Ventilation

This study is ongoing, but not recruiting participants.

Sponsor:

The Cleveland Clinic

ClinicalTrials.gov Identifier:

NCT01532245

First Posted: February 14, 2012

Last Update Posted: December 16, 2016

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One method for treating intraoperative hypoxia during one-lung ventilation (OLV) is application of PEEP to the dependent lung. However, only a minority of patients benefit from this maneuver. The effect of applied PEEP on oxygenation depends on the relation between the total end-expiratory pressure and the lower inflexion point (LIP) of pressure-volume curve (1). LIP during OLV can be determined with super-syringe technique, but is too complicated for routine operating room use. An alternative is the constant-flow method which is easy and widely used in intensive care settings (2). The investigators goal was to confirm that the constant-flow method as applied by an intensive care ventilator works during OLV.

Methods: After IRB approval and written, informed consent, data were obtained from 20 patients during OLV for thoracic surgery who were ventilated with an AVEA (VIASYS Healthcare) critical-care ventilator. During two-lung ventilation (TLV) and OLV 8 ml•kg-1 tidal volume was used. During OLV, ventilation periods of ten minutes, with and without 5 cmH2O PEEP were alternated. During each period, the investigators recorded arterial blood partial pressures, respiratory and hemodynamic values, intrinsic PEEP (PEEPi), and LIP. PEEPi and LIP were determined using the automatic mode of the ventilator; specifically, LIP was determined with a continuous flow of 3L/minute.

Relationship between the net change of lower inflexion point (LIP)- positive end-expiratory pressure (PEEPi) ditstance with and without positive end-expiratory pressure (PEEP) and change of PaO2 is useful during OLV for determination of patients reaction for application extternal positive end-expiratory pressure (PEEP)

Relationship between the net change of lower inflexion point (LIP)-intrinsic positive end-expiratory pressure (PEEPi) ditstance with and without positive end-expiratory pressure (PEEP) and change of PaO2 is useful during one lung ventillation (OLV) for determination of patients reaction for application external positive end-expiratory pressure (PEEP).

During OLV, ventilation periods of ten minutes, with and without 5 cmH2O positive end-expiratory pressure (PEEP) were alternated

Eligibility

Information from the National Library of Medicine

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Ages Eligible for Study:

18 Years and older (Adult, Senior)

Sexes Eligible for Study:

All

Accepts Healthy Volunteers:

No

Criteria

Inclusion Criteria:

thoracic surgery lung ventillation

Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01532245

Locations

Hungary

University of Debrecen, Medical and Health Science CenterDepartment of Anesthesiology and Intensive Care